LEADS BIOLABS-B - VOLUNTARY ANNOUNCEMENT

PARTNER OBLENIO CLOSES OVERSUBSCRIBED US$62 MILLION SERIES B FINANCING ROUND TO ACCELERATE CLINICAL DEVELOPMENT OF LBL-051

Nanjing Leads Biolabs Co., Ltd.

南京維立志博生物科技股份有限公司

(A joint stock company established in the People's Republic of China with limited liability)

(Stock Code: 9887)

VOLUNTARY ANNOUNCEMENT

PARTNER OBLENIO CLOSES OVERSUBSCRIBED US$62 MILLION SERIES B FINANCING ROUND TO

ACCELERATE CLINICAL DEVELOPMENT OF LBL-051

This announcement is made by Nanjing Leads Biolabs Co., Ltd. (the "Company", together with its subsidiaries, the "Group") on a voluntary basis to inform shareholders and potential investors of the Company about the latest business development of the Company.

Company is pleased to announce that its JV company with Aditum Bio, Oblenio Bio ("Oblenio"), has successfully closed an oversubscribed $62 million Series B financing round (the "Series B"). The Series B was led by Pfizer Ventures, with participation from Deep Track Capital, GV and Aditum Bio, Oblenio's founding investor. This milestone will significantly advance the clinical development of LBL-051, LBL-051 is Oblenio's sole asset, and is a CD19/BCMA/CD3 trispecific T-cell engager antibody designed to offer a novel treatment option for patients with severe autoimmune diseases through immune resetting.

LBL-051 was developed using the Company's proprietary LeadsBodyTM platform. By simultaneously targeting BCMA, CD19 and CD3, LBL-051 is designed to achieve broader depletion of pathogenic B cells and plasma cells compared to mono-specific or bi-specific antibodies, with the potential to deliver deeper and more durable responses. This immune reset strategy aims to help patients with refractory autoimmune diseases achieve long-term drugfree remission.

Oblenio recently presented preclinical data at the 2026 European Congress of Rheumatology (EULAR 2026) showed that step-up dosing of LBL-051 resulted in complete depletion of peripheral and tissue B-cells and plasma cells in non-human primate models, with the emergence of immature, non-memory B cells upon recovery — an immunological profile consistent with observations in autoimmune patients achieving long-lasting drug-free remissions in the clinic. Importantly, the study showed that the treatment did not cause cytokine release syndrome (CRS), including at high exposure levels, and demonstrated dosedependent decreases in peripheral blood immunoglobulins, consistent with plasma cell depletion. Based on these data, Oblenio is moving rapidly toward clinical trial initiation.

With the closing of the Series B, Dr. Kang Xiaoqiang, our founder, chairman and chief executive officer, will serve as a board observer of Oblenio, further deepening the strategic collaboration between the two parties. As the originator of LBL-051, the Company will continue to provide technical support to Oblenio, and will be entitled to milestone payments and sales royalties as LBL-051 advances through global clinical development and commercialization.

LISTING RULE IMPLICATIONS

Prior to the Series B, the Company held indirect 10% equity interest in Oblenio. Given that Oblenio is not a subsidiary of the Company, such deemed disposal is not a transaction under Chapter 14 of the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited.

Cautionary Statement required by Rule 18A.05 of the Rules Governing the Listing of

Securities on The Stock Exchange of Hong Kong Limited: The Company cannot guarantee that it will be able to develop, or ultimately market, LBL-051, successfully. Shareholders and potential investors of the Company are advised to exercise due care when dealing in the shares of the Company.

By order of the Board

Nanjing Leads Biolabs Co., Ltd.南京維立志博生物科技股份有限公司Dr. KANG XIAOQIANG

Chairman, Executive Director and

Chief Executive Officer

Nanjing, PRC, June 25, 2026